Process for producing molybdenum alloys



-Patented Nov. 1,

UNITED STATES PATENT OFFICE PROCESS FOR PRODUCING MOLYBDENUM ALLOYS Arthur Linz, New-York, N. Y., assignor to Climax Molybdenum Company, New York, N. Y., a corporation of Delaware No Drawing. Application April 28, 1937, Serial No. 139,504

3 Claims. (Cl. -133) The present invention relates to a novel and improved process of producing molybdenum containing alloy, and more particularly to the production of molybdenum containing ferrous alloys.

- Objects and advantages of the invention will be set forth in part hereinafter and in partwill be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.

The invention consists in the novel compositions, steps, combinations and improvements herein shown and described.

It has heretofore been customary to introduce molybdenum into a ferrous alloy by the addition of ferromolybdenum to the molten steel or other metal, or by the addition of calcium molybdate, or a similar salt of a molybdenum acid, to the molten metal or furnacecharge, and this procedure has been followed for blast furnace 'practice as well as with electric furnaces and other melting processes. Lower calcium salts of molybdic acid have also been employed, and othersalts of molybdic acid have been used successively, but for economical production calcium molybdate has been favored. All of these processes are characterized by the ,use of a less volatile form of molybdenum than-the oxide and the usual process involves the preparation'of molybdenum trioxide from molybdenite, and the conversion of the oxide into the salt by roasting or wetting the oxide and calciumoxide.-

According to the present invention, the molybdenum trioxide is not converted into a molybdate before use, but is merely mechanically mixed with ,an oxide or oxide producing salt and this mechanicalmixture is added to the blastfurnace,

electric furnace or other apparatus ,by which 0 vention, recovery of the molybdenum is nearly the ferrous metal is to be melted. -Thereby is avoided the separate and distinct stepof roastmg or otherwise reacting the molybdenum oxide with the fixative calcium or other oxide and a -co rresponding economy is effected without any countervailing defect. By the process of the present invention, the recovery of the molyb-- denum is at leastas great in the alloy as wit calcium molybdate. l

According to extended tests of the present in- -quantitative or 100 per cent.

The mechanical mixture of the moybdenum oxide and lime, or other volatilization-prevent-" ing oxide when added to thecharge, first combines to form the corresponding molybdate which then reacts and dissolves in the molten metal. Preferably, the mixture comprises the stoichiometrical quantities 'of the substances although where an excess of slag is not objectionable, an excess of lime maybe employed.

A substantially complete list of the various oxides and carbonates which may be employed in combinationwith the molybdenum oxide includes the-alkaline earth oxides (magnesium, calcium, barium and strontium oxides), cupric oxide oxide '(CeOz) and ferrous oxide (FeO) and the corresponding carbonates. v

.(CuO), beryllium oxide, lead oxide (PbO), ceric 15 It is alsopossible to use certain natural min-- erals in place of the lime, etc.; and natural ferrous carbonate, siderite, spathic iron or chalybite may be used. Also certain silicides such as barium or calcium silicide may be used.

Having thus described this invention in connection with illustrative embodiments thereof, to the details of which I do not desire to be limited, what is claimed as new and what is desired to secure by Letters Patent is set forth in the appended claims.

.heating to reduce the molybdenum and recover it in the metal. I 3. A process of producing molybdenum containing ferrous alloys which includes adding to the metal, to be alloyed a mechanical mixture of a molybdenum oxide and an alkaline earth oxide and recovering the molybdenum by heating the metal-and mixture. e 

